Dundon 321SS Lifetime Center Muffler for 997/991
09-15-2017, 07:19 PM
#76
Any power lose on the "quiet" exhaust?
09-15-2017, 07:23 PM
#77
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That was one of the design criteria for the Quiet muffler, no power loss. We use a larger diameter tube than the OEM muffler and we add dB elements to the tube and around the tube (don't want to give away too much...). So short answer is no power loss from the quiet muffler...
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Dundon Motorsports
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Dundon Motorsports
Gig Harbor, WA
253-200-4454
jamie@dundonmotorsports.com
www.dundonmotorsports.com
Facebook.com/dundonmotorsports
Instagram @dundon_motorsports
09-15-2017, 10:15 PM
#78
Drifting
In our testing we saw 10-12dB reduction at the ridge. From 104 with the OEM muffler down to 92-93 with the Orange (Quiet) Center Muffler. The all 4 cars that were tested passed at Laguna. 2 997' GT3's one with side mufflers one with side deletes. And 2 991 GT3 again one stock and one with side deletes all passed at 92dB.
no guarantees that your car will pass Laguna, but all the testing we've seen does pass.
no guarantees that your car will pass Laguna, but all the testing we've seen does pass.
09-16-2017, 02:30 AM
#79
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We measured our race headers and quiet muffler at the Ridge here locally at 92-93dB without using turnaways, on the front straight. Without the quiet muffler the car was 102-104dB at the same place
Side Muffler deletes do make the car a bit louder as there is a small expansion of the gasses that occurs in the side mufflers even with the valves open.
Our catted header systems and quiet mufflers will be the hot ticket for a quiet powerful car. (997 catted header prototypes slated by the end of the month).
Last edited by Jamie@dundonmotorsports; 09-16-2017 at 02:55 AM.
03-16-2019, 11:57 AM
#80
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bump - another day at Laguna - 4 GT3's present - 92 DB limit - the other 3 GT3's could _NOT_ make sound - none of them got any more than 4 Laps - even the one with the GPS based exhaust solution…but I ran my sessions full tilt - no lift - no upshift - full fun - the Dundon quiet muffler for your GT3 saves track days.
I also past a 90 DB limit day in November of 2018 with PCA Diablo region - I did get pop'd at the end of the day on cool down lap last session when I idled past the sound both (92.5) on full cool down - previous lap was full tilt flat throttle 3rd gear - but the cool down lap I got sound!
https://rennlist.com/forums/991-gt3-...f-silence.html
I also past a 90 DB limit day in November of 2018 with PCA Diablo region - I did get pop'd at the end of the day on cool down lap last session when I idled past the sound both (92.5) on full cool down - previous lap was full tilt flat throttle 3rd gear - but the cool down lap I got sound!
https://rennlist.com/forums/991-gt3-...f-silence.html
03-16-2019, 03:01 PM
#81
Drifting
bump - another day at Laguna - 4 GT3's present - 92 DB limit - the other 3 GT3's could _NOT_ make sound - none of them got any more than 4 Laps - even the one with the GPS based exhaust solution…but I ran my sessions full tilt - no lift - no upshift - full fun - the Dundon quiet muffler for your GT3 saves track days.
I also past a 90 DB limit day in November of 2018 with PCA Diablo region - I did get pop'd at the end of the day on cool down lap last session when I idled past the sound both (92.5) on full cool down - previous lap was full tilt flat throttle 3rd gear - but the cool down lap I got sound!
https://rennlist.com/forums/991-gt3-...f-silence.html
I also past a 90 DB limit day in November of 2018 with PCA Diablo region - I did get pop'd at the end of the day on cool down lap last session when I idled past the sound both (92.5) on full cool down - previous lap was full tilt flat throttle 3rd gear - but the cool down lap I got sound!
https://rennlist.com/forums/991-gt3-...f-silence.html
03-16-2019, 10:12 PM
#82
Rennlist Member
bump - another day at Laguna - 4 GT3's present - 92 DB limit - the other 3 GT3's could _NOT_ make sound - none of them got any more than 4 Laps - even the one with the GPS based exhaust solution…but I ran my sessions full tilt - no lift - no upshift - full fun - the Dundon quiet muffler for your GT3 saves track days.
I also past a 90 DB limit day in November of 2018 with PCA Diablo region - I did get pop'd at the end of the day on cool down lap last session when I idled past the sound both (92.5) on full cool down - previous lap was full tilt flat throttle 3rd gear - but the cool down lap I got sound!
https://rennlist.com/forums/991-gt3-...f-silence.html
I also past a 90 DB limit day in November of 2018 with PCA Diablo region - I did get pop'd at the end of the day on cool down lap last session when I idled past the sound both (92.5) on full cool down - previous lap was full tilt flat throttle 3rd gear - but the cool down lap I got sound!
https://rennlist.com/forums/991-gt3-...f-silence.html
Stock headers or aftermarket?
03-16-2019, 10:21 PM
#83
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Dave has a completely stock exhaust with the exception of our Lifetime Quiet Muffler. We have had some success with our catted headers passing with a quiet muffler and 997’s with side deletes running our quiet muffler passing.
Passing sound at Laguna is pretty fickle. So the most cautious route, if you want to track there with no issues, is the best course
Passing sound at Laguna is pretty fickle. So the most cautious route, if you want to track there with no issues, is the best course